1. Field of the Invention
The present invention relates to a medical manipulator that includes a needle mounted on the tip end of a shaft for supplying microwave energy to perform a surgical technique on an affected region of a patient, and also to a medical robot system incorporating such a medical manipulator.
2. Description of the Related Art
Electrosurgical knives and laser knives mainly are used to solidify, stop bleeding, and cut off affected and surrounding regions in patients. Recently, there has been proposed a medical apparatus employing microwaves. The proposed medical apparatus includes a needle for piercing a living body and a means for supplying microwave energy to the needle so as to enable the needle to generate thermal energy to perform a surgical technique, such as tissue solidification, blood stanching, or the like, on the living tissue (see, for example, Japanese Patent Publication No. 1-020617 and Japanese Patent Publication No. 1-020619).
A medical apparatus of the type described above is capable of easily stopping bleeding and thermally modifying living tissue without causing the living tissue to be carbonized. Heat that is generated in the tissue by microwaves kills bacteria and prevents wasteful bleeding.
According to a recent endoscopic surgical operation process, small holes are opened in the abdominal region, for example, of a patient, and an endoscope and manipulators or forceps are inserted into such holes. The surgeon performs a surgical operation on the patient with the manipulators or forceps, while watching an image captured by the endoscope and displayed on a display monitor. Since the endoscopic surgical operation process does not require a laparotomy to be performed, the operation is less burdensome on the patient and greatly reduces the number of days required for the patient to spend in the hospital before recovering from the operation and being released from the hospital. Therefore, the range of surgical operations in which the endoscopic surgical operation process may be applied is expected to increase.
As disclosed in Japanese Laid-Open Patent Publication No. 2002-102248 and Japanese Laid-Open Patent Publication No. 2003-061969, a manipulator system comprises a manipulator and a controller for controlling the manipulator. The manipulator comprises an operating unit, which is manually operated, and a working unit replaceably mounted on the operating unit.
There has also been proposed a medical robot system for actuating a medical manipulator with a robot arm (see, for example, U.S. Pat. No. 6,331,181). The medical robot system can be remotely controlled by a master arm, and can be moved in various ways under a programmed control.
The medical robot arm has a plurality of robot arms, which can selectively be used depending on the surgical technique required. One of the robot arms incorporates an endoscope therein for capturing an image representing the inside of a body cavity, which is capable of being visually confirmed on a display monitor.
The literature, “Improvement on the input impedance of a coaxial-slot antenna for interstitial heating by loading a matching circuit”, by Shinya Okabe and three others, IECEI transactions 2004/10, Vol. J87-B, No. 10, pp. 1741-1748, shows a medical coaxial slot antenna for interstitial heating, which is combined with a matching circuit for matching the input impedance. The coaxial slot antenna has two slots capable of producing a locally heated region, another slot (matching slot) for impedance matching, and a metal pipe covering the matching slot.
The medical apparatus disclosed in Japanese Patent Publication No. 1-020617 and Japanese Patent Publication No. 1-020619 basically is premised on a laparotomy operation, and does not take into account endoscopic surgical operations using forceps. There has heretofore been proposed an electrosurgical knife, which is mounted on the tip end of forceps and connected to electric wires. However, even if the electrosurgical knife is replaced with a needle for supplying microwaves, since microwave energy tends to radiate from the electrical wires, the assembly is considerably inefficient.
If microwaves are supplied to a plurality of needles, which are appropriately spaced apart from each other, then it may be contemplated that the needles can perform a surgical technique over a wide region, thereby resulting in a synergetic effect and a shortened operation time. However, in endoscopic surgical operations, since forceps are inserted through narrow trocars, even if needles are mounted onto the tip ends of such forceps, the distance between the needles is limited.